EP2229853A1

EP2229853A1 - Milk frothing device

Info

Publication number: EP2229853A1
Application number: EP09155628A
Authority: EP
Inventors: designation of the inventor has not yet been filed The
Original assignee: Green Lane Products Ltd
Current assignee: Green Lane Products Ltd
Priority date: 2009-03-19
Filing date: 2009-03-19
Publication date: 2010-09-22
Also published as: US8726790B2; EP2408341B1; WO2010106372A1; EP2408341A1; US20120167781A1

Abstract

Milk frothing device comprising a housing (2) including a container (10) for receiving the milk to be frothed, an agitation means (20), wherein the container comprises a side wall (11), a bottom portion (13) and an inclined wall portion (12), wherein the inclined wall portion being inclined with respect to the side wall and being confined by the side wall and the bottom portion, wherein the container and the agitation means together form an asymmetrical arrangement.

Description

Field of the invention

The present invention relates to a device for frothing milk, and in particular to a milk frothing device which provides for an improved frothing process.

Background of the invention

In recent times, preparing warm beverages including coffee and hot chocolate becomes more and more popular. These beverages beside coffee often also include frothed milk as ingredience. For this purpose, different concepts of milk frothing devices have been provided, some of which provide for a container for receiving the milk to be frothed as well as a stirring device, which will be used to produce frothed or foamed milk. Several of these devices also include a heater, in order to combine the heating and the frothing process.
From US 2007/0221068 for example an appliance for preparing a froth from a milk-based liquid is known, which includes a tank for receiving liquid that is to be frothed, and in which liquid a rotatable stirrer is positioned, a stand associated with the tank, and a system for driving this stirrer. The stirrer drive system and the stirrer include magnetic elements allowing the stirrer to be rotationally driven magnetically in the tank. Disturbance member are provided to break or prevent symmetric circulation of the liquid about the median vertical axis of the tank.
Further, from EP 1 987 750 an appliance for warm milk preparation is known consisting of a reservoir for the milk, a removable cover with frother and electric circuit opportunely fed and controlled automatically by means of a temperature sensor.
Further, US 2001/0036124 provides for a beverage container with integrated stirring device, which provides for a drinking container cup, such as for coffee, tea, soup or the like, having an interior and an exterior surface, said container having an integrated powered stirring device extending from the interior surface of the bottom section of the housing and driven by a small battery powered motor located in the bottom section of the housing.
All of the devices provide for a single stirring device, which brings the milk into a rotation leading to a swirl, so that in the rotational axis, normally the median vertical axis, the milk level decreases, wherein the milk level apart from the median vertical axis increases. For devices with a de-central stirring device, this may also lead to an oscillation leading to a further increase of the milk level at the side wall owing to centrifugal force, so that the milk slops and is not available for the frothing process anymore, this is particularly the case for larger quantities above 100 ml of milk. Even if particular obstacles are provided for reducing the swirl effect, those obstacles described in the prior art lead to a geometry, which is very difficult to clean up.
Therefore, there may be a need to provide a milk frothing device which provides for an improved frothing process, in particular by providing a milk frothing device which does not lead to a slop of the milk contained in the milk container.

Summary of the invention

In view of the above, it would be desirable to provide an improved milk frothing device over the prior art, which provides for an optimized frothing process.
The present invention provides for a device according to the subject-matter of the independent claim, wherein further embodiments are incorporated in the dependent claims.
According to an exemplary embodiment of the invention the milk frothing device comprises a housing including a container for receiving the milk to be frothed, an agitation means, wherein the container comprises a side wall, a bottom portion and an inclined wall portion, wherein the inclined wall portion being inclined with respect to the side wall and being confined by the side wall and the bottom portion, wherein the container and the agitation means together form an asymmetrical arrangement.
Thus, it can be achieved that due to the asymmetrical arrangement in combination with the inclined side wall, the milk or any other liquid in the container will not increase in level during the agitation. Although the agitation means may provide for a rotation of the milk or liquid in the container, the asymmetrical arrangement of the agitation means and the container geometry may keep the maximum level of the milk or liquid low. Further, a sufficient mixing and distribution of the milk will take place so that every portion of the milk will pass the agitation means. In particular by providing the inclined wall portion, this wall portion will compensate the level increasing effect of the rotation by the agitation means, as well as the oscillation of the milk level. The inclined wall portion together with the side wall and the bottom portion provides for a surface which is easy to clean, since no further obstacles are necessary for suppressing the oscillation of the milk within the container. In should be noted that nevertheless additional obstacles or protrusions can be provided, in particular in form of a particular side wall structure of the container. Such a side wall construction may for example be elongated protrusions in a circumferential direction in an even or screw like manner, in order to avoid the increasing of the level of the milk owing to a swirl effect.
It should be noted that an inclined wall portion is inclined with respect to a vertical side wall and a horizontal plane as well, so that the inclined wall portion may be in form of a slope or flange. It should also be noted, that the inclined wall portion can as an alternative also be provided between a lower side wall and an upper side wall, as well as the inclined wall portion can also constitute a fully inclined bottom, wherein a bottom portion then constitutes the lowest portion in the container.
According to an exemplary embodiment of the invention the agitation means is positioned opposite to the inclined wall portion.
This provides for a kind of damping effect with respect to the centrifugal forces of the rotating milk from the agitation means. By providing the agitation means opposite to the inclined wall portion, the agitation means can be provided in the vicinity of the inclined wall portion allowing to immediately damp the oscillating tendency of the rotating liquid or milk.
According to an exemplary embodiment of the invention the agitation means comprises an agitator and a rod, wherein the agitator is mounted to a first end of the rod, wherein the container comprises a duct, wherein the rod extends through the duct so that the agitator is provided within the container.
Thus, the agitator can be driven by a rod extending through a duct to the outside of the container, so that a driving means for driving the agitator or the agitation means in general must not be provided within the container. It should be noted that the rod may also be divided into parts having a hinge coupled in between, in particular when the rotational axis of a driving means and the rotational axis of the agitation means are inclined or offset.
According to an exemplary embodiment of the invention the duct is provided at the bottom portion of the container.
Thus, it is easy to mount the agitation means and the driving means in a vertical axis, in particular when the bottom portion is a flat and horizontal portion with respect to the normal operating position of the milk frothing device. However, it should be noted that the duct may also be provided in the inclined portion, which allows to incline the total frothing process, which may also reduce the oscillating of the milk or liquid as well as the increasing of the milk level during frothing. In particular, when providing the duct in the inclined surface, gravitational forces may provide for additional damping of the oscillating effect together with an asymmetrical arrangement.
According to an exemplary embodiment of the invention, the rod on a second end is provided with a first mechanical coupling element.
This allows to couple and to decouple the agitation means or the agitator to or from a driving means. This is for example of relevance, if the container should be removed from the driving means, for serving the frothed milk, so that not the complete milk frothing device but only the container or the housing can be handled, which is much more convenient than taking the whole milk frothing device. The mechanical coupling element may be for example a kind of rubber plate, a gear or a coupling blade cock. If using a rubber as a surface, such a coupling device is easy to be coupled in a force fit manner to a counter part. It should be noted that also a kind of rubber lamella or rubber pins may serve as a coupling surface of the first mechanical coupling element. In particular an automatically engaging coupling element can be used so that the user does not have to take care on the correct coupling position.
According to an exemplary embodiment of the invention, the housing further includes a heating element, wherein the heating element being attached to at least an inclined wall portion.
Thus, the heating of the milk within the container can be proceeded at the same time as the frothing process, so that both the heating and the frothing can take place in parallel in order to save time. This is in particular of relevance under domestic and professional aspects in gastronomy.
According to an exemplary embodiment of the invention, the inclined wall portion is provided off-centre.
The off-centre location of the inclined wall portion serves for an improved asymmetric geometry, which reduces the oscillation of the milk or liquid in the container.
According to an exemplary embodiment of the invention, the inclined wall portion is flat.
This provides in particular for an improved cleaning effect, and further allows for easier mounting a heating element at the back of the inclined wall portion of the container.
The wall portion may have an inclination of about 45° ± (plus/minus) 15° with repect to a virtual horizontal plane during normal operation. Thus, oscillation of the rotating milk can be significantly reduced. The size of the inclined surface may be for example 50 % of the size of a surface of the bottom portion of the container. In other words, the amount of the surface of the bottom portion and the amount of a surface of the inclined wall surface may be in a similar dimension or may deviated from each other of up to about 20 %. In particular, the amount of the inclined wall surface may be somewhat larger than the amount of the horizontal bottom surface.
According to an exemplary embodiment of the invention, the agitation means is provided off-centre of the container.
In particular, for those embodiments having a horizontal bottom portion, the off-centre agitation means can be provided with the rod being in a vertical direction. In combination with the inclined surface being off-centre, the agitation means also being off-centre can provide for a reliable damping of the oscillation and therefore avoid for an unintentionally increasing of the milk level during the frothing process.
According to an exemplary embodiment of the invention, the side wall portion is of cylindrical form and the bottom portion is flat, wherein the duct is provided in the flat bottom portion. In particular, if the side wall portion is of cylindrical form and the bottom portion is flat, an optimized volume ratio of the container content and the size of the total milk frothing device may be obtained.
According to an exemplary embodiment of the invention, the milk frothing device further comprises a releasable base portion for receiving the housing, wherein the base portion being provided with a driving means, wherein the driving means is provided with a second mechanical coupling element, wherein the second coupling element is adapted for being coupled to the first coupling element when the base portion receiving the housing.
Thus, a driving means, for example a motor or a spring or the like can be maintained in the base portion, wherein the container and the housing of the milk frothing device can be handled for an easier serving. The second mechanical coupling element may be in particular designed for receiving the first mechanical coupling element in order to provide for an optimum transmission of the torque from the driving means to the agitator. The second mechanical coupling element may be for example designed in an identical manner as the first mechanical coupling element, which reduces the manufacturing costs owing to identical coupling elements. However, the second mechanical coupling element may also be made of a different surface being particularly adapted to form a force fit connection between the first and second mechanical coupling element.
According to an exemplary embodiment of the invention, the housing further includes a first electrical coupling element connected to the heating element, wherein the base portion comprises a second electrical coupling element, wherein the second electrical coupling element is adapted for being coupled to the first electrical coupling element when the base portion receiving the housing.
For this purpose, also the complete electrical connections for a power supply can be provided in the base portion, so that for an easier handling, no wired connections remain, wherein all functional couplings, e.g. electrical coupling and mechanical coupling takes place when the base portion receiving the housing.
According to an exemplary embodiment of the invention, the second electrical coupling element is provided off-centre of the base portion.
This provides an easier handling for the user, in particular when the second electrical coupling element is provided closed to the edge of the base portion. Thus, the user can recognize how to couple the base portion and the housing of the milk frothing device in order to ensure that not only the electrical connection but also the mechanical connection takes place between the base portion and the housing of the milk frothing device. A recess in the housing corresponding to a protruded socket in the base portion, in particular close to the edge, provides for an easier handling and ensures that the respective electrical and mechanical connections are established for a safe use.
According to an exemplary embodiment of the invention, the housing includes the duct, the heating element, the first electrical coupling element and the first mechanical coupling element sealed in a dishwasher proved manner.
This can for example be obtained by a casting, molding or other sealing between a bottom portion and an outer portion of the housing, so that a sealed interior of the housing can be established. This allows for example to put the housing including the container and the agitation means into a dishwasher, but to maintain the main electrical components as the operation bottom, a printed circuit board and the motor outside the dishwasher, since usually, only the interior of the housing will be contaminated with milk or liquid during normal use.
According to an exemplary embodiment of the invention, the container comprises a filling volume of at least 185 ml.
Thus, a plurality of beverages can be prepared simultaneously using foamed or frothed milk. It should be noted that the filling volume of the container is defined as the volume of milk or liquid which can be received without slopping during normal operation of the milk frothing device. In other words, the filling volume may also be increased by only keeping low the liquid level in normal use. The absolute volume of prior art devices may be the same or larger, however by providing the asymmetrical arrangement according to the invention, the filling volume of the inventive device can be much larger. Thus the frothing device can be designed smaller than comparable devices in the prior art.
According to another aspect of the present invention there is provided a milk frothing device comprising a housing including a container for receiving the milk to be frothed, an agitation means and a releasable base portion for receiving the housing, wherein the agitation means is provided with a first mechanical coupling element, wherein the base portion being provided with a driving means, wherein the driving means is provided with a second mechanical coupling element, wherein the second coupling element is adapted for being coupled to the first coupling element when the base portion receiving the housing.
Thus, a housing portion of a milk frothing device can be released from a base portion, so that the housing of the milk frothing device can be used for an easier handling for serving frothed milk. The same way, a first mechanical coupling element can be released from a second mechanical coupling element, so that the first mechanical coupling element remains at the housing portion, wherein the second mechanical coupling element remains at the base portion of the milk frothing device. Thus, all sensitive elements of the milk frothing device, in particular the motor and the main electrical components remain at the base portion, wherein the housing of the milk frothing device can easily be handled and also be dropped into a dishwasher or in a basin for cleaning, without effecting the sensitive elements like the motor and the electrical contacts and controlling components and switching elements.
According to an exemplary embodiment of the invention the agitation means comprises an agitator and a rod, wherein the agitator is mounted to a first end of a rod, and wherein the container comprises a duct, wherein the rod extends through the duct, so that the agitation means is provided within the container, and the rod on a second end is provided with a first mechanical coupling element.
According to an exemplary embodiment of the invention, the duct is provided at the bottom portion of the container, as already described above. The duct together with the rod may constitute a slide bearing.
According to an exemplary embodiment of the invention, the container comprises a side wall, a bottom portion and an inclined wall portion, wherein the inclined wall portion being inclined with respect to the side wall and being confined by the side wall and the bottom portion. Thus, a swirl owing to a circular movement of the milk leading to a slop can be damped, so that the milk level does not increase so much owing to the damping effect of the inclined wall portion as described above. This may also lead to an optimized mixing of the milk to let pass the agitator all portions of the milk.
According to an exemplary embodiment of the invention, the housing further includes a heating element, wherein the heating element being attached to the container. Thus, both processes can be conducted in parallel, the frothing process and the heating process of the milk or any other beverage or liquid in the container.
According to an exemplary embodiment of the invention, the housing further includes a first electrical coupling element connected to the heating element, wherein the base portion comprises a second electrical coupling element, wherein the second electrical coupling element is adapted for being coupled to the first electrical coupling element when the base plate receiving the housing. Thus, also a releasable connecting of the heating element with the base portion can be carried out, as described above.
According to an exemplary embodiment of the invention, the housing includes the duct, the heating element, the first electrical coupling element and the first mechanical coupling element sealed in a dishwasher proved manner, as described above.
According to an exemplary embodiment, the container further comprises an opening for filling in and pouring out milk to be frothed. This opening can be covered by a cover. This cover may also be provided with a seal to avoid slopping and to provide a tight fixing of the cover.
It should be noted that the above features may also be combined, wherein the combination of the above features may also lead to a synergetic effect, even if not explicitly described in detail.
These and other aspects of the present invention will become apparent from and elucidated with reference to the embodiments described herein after.

Brief description of the drawings

Exemplary embodiments of the present invention will be described in the following with reference to the following drawings:

Fig. 1 illustrates a milk frothing device according to an exemplary embodiment of the invention having a housing and a base portion, wherein the base portion received the housing of the milk frothing device.
Fig. 2 illustrates a milk frothing device according to an exemplary embodiment of the invention, wherein the housing portion is released from the base portion of the milk frothing device.
Fig. 3 illustrates a cross-sectional view of an exemplary embodiment of the milk frothing device.
Fig. 4 illustrates a further embodiment of the invention wherein the agitation means is provided in the inclined wall portion.
Fig. 5 illustrates an embodiment of the invention, wherein the inclined wall portion is flatter.
Fig. 6 illustrates an embodiment of the invention, wherein the inclined wall portion is steeper.
Fig. 7 illustrates an embodiment of the invention, wherein the inclined wall portion extends over the complete width of the container.
Fig. 8 illustrates an embodiment of the invention including elongated protrusions.

Detailed description of exemplary embodiments

Fig. 1 illustrates a milk frothing device 1 with a housing 2 and a base portion 3 according to a exemplary embodiment of the invention in a combined position. The milk frothing device 1 comprises a housing portion 2 and a base portion 3, wherein the housing portion 2 can be released from the base portion 3. The housing portion may comprise a handle 4, which may provide for an easier handling of the housing portion of the milk frothing device 1. In order to maintain the heat within a container of the milk frothing device, the milk frothing device 1 can be provided with a cover 16. The cover may be provided as a transparent cover in order to monitor the frothing process within the container of the milk frothing device.
The frothing process may be started with an operation bottom 42, which may be provided at the base portion 3 of the milk frothing device 1. When pushing the operating bottom, the heating process will be started e.g. synchronously to a frothing process within the container. When a particular temperature is reached, the heating process will stop in order to avoid overheating of the milk. The frothing process may also be stopped depending on the temperature of the milk, however, the frothing process may also be stopped after a particular lapse of time. It should be noted that also for the frothing process particular sensors 18 may be provided within the housing, in order to monitor the success of the frothing process, for example by a ultrasonic sensor, which can monitor the acoustic properties within the container depending on the foam development of the frothed milk.
Fig. 2 illustrates a milk frothing device 1 as already depicted in Fig. 1, however, in a released situation, where the housing portion 2 of the milk frothing device 1 is released from a base portion. When releasing the housing portion 2 from the base portion 3, a contact 31 on the housing portion side can be released from a contact 41 on the base portion side. When providing the plug/socket 31/41 at the edge of the housing portion 2 and the edge of the base portion 3, respectively, a user can easy monitor when putting the housing portion 2 onto the base portion and to receive the correct positioning thereof. It should be noted that the plug/socket 31/41 can also be provided as a separate unit and that a separate forming of the edge of the base portion corresponding to the edge of the housing portion may be provided for providing an easier fit of housing 2 and the base portion 3. When releasing the housing portion 2 from the base portion 3, a frothing process and a heating process may be stopped automatically. A particular electronic in the base portion may detect the releasing of the housing portion, in order to interrupt the circuit to provide the heater with electrical current. A base portion may be provided with a connector plug to the grid, which, however, is not illustrated in the Figures.
Fig. 3 illustrates an exemplary embodiment of a milk frothing device 1 according to the present invention. The milk frothing device 1 comprises a housing portion 2 and a base portion 3. The housing portion 2 may be released from the base portion 3 in order to provide an easier handling of the housing portion during serving milk or other frothed beverages in the container 10. The container 10 in the illustrated embodiment comprises a cylindrical side wall portion 11, an inclined wall portion 12 and a bottom portion 13. However, it should be noted that in particular the side wall portion 11 may also be of a different shape and does not have to be formed in a cylindrical shape. In the shown embodiment, a duct 14 is provided in the bottom portion 13 of the container 10 in order to provide a duct for a rod 22 of an agitation means 20. The agitation means 20 comprises an agitator 21, which may be provided as a circular metal ring with a coil wounded around the ring in order to provide an improved frothing process. The agitator 21 is provided at one end of the rod 22, wherein on the other end of the rod 22 there is provided a coupling element 23. The coupling element may engage with a corresponding coupling element 53 of the base portion 3, when the housing 2 is received on the base portion 3. When releasing the housing portion 2 from the base portion 3, the connecting portion 23 will also be released from the connecting element 53. It should be noted that even if not shown, there may also be provided some spring or resilient members, which provide for a sufficient mechanical coupling between the coupling element 23 and the coupling element 53.
The base portion 3 comprises a drive means 50, which in the present embodiment further comprises a motor 51 and a rod 52 being connected to the motor. The second mechanical coupling element 53 is mounted to the end portion of the rod 52. The housing portion 2 further comprises a first electrical coupling element 31 which correspondingly engages into a second electrical coupling element 41 of the base portion 3. This connection between the coupling elements 31 and 41 provides for an electrical contact between the base portion 3 and the housing portion 2 in order to provide a heating element 30 with electrical energy. It should be noted that the electrical connection between the first electrical coupling element 31 and the heating element 30 is not shown in Fig. 3. It should be noted that a heating element may be a conventional heating element as well as a heating film or a micro wave device. The heating element may be at least partially provided at the inclined wall portion of the container 10, in order to provide a heating impact to the milk or liquid contained in the container 10. The container may be fixed to the housing portion by a press fitting or welding or soldering process at the top portion of the housing 2. It should be noted that the space between the housing 2 and the container 10 may also be filled with an insulating material in order to avoid a heat loss from the inside of the container to the outside. The housing portion 2 may also comprise a cover 16, which may be sealed by a circumferential seal 17 to the container 10.
The base portion 3 may comprise a frame construction 72, which may be covered by an outer shell 71, which may for example be provided as a design surface of the base portion.
Further, inside the base portion 3 there may also be provided a printed circuit board 60, which may include a control circuit for controlling the driving means as well as the heating element. Onto the printed circuit board, also electronics can be provided which control particular sensors (not shown) which may control a sufficient heating process to not overheat the milk to be foamed, and sensors 18 which may monitor a sufficient foaming process. Foaming sensors may for example be ultrasonic sensors measuring the acoustic properties of the foamed milk, which will substantially change between a foamed and an un-foamed condition, since foamed or frothed milk has a very much higher acoustic damping coefficient compared to un-frothed milk. However, as an alternative, also visual sensors may be provided in order to monitor the filling level of the container 10. Frothed milk has a larger volume than un-frothed milk, so that based on the filling level of the container, a frothing process may be monitored. Further, a frothing process can be stopped when filling too much milk into the container 10, so that the milk frothing device can also be operated with an open cover, without the risk that the foamed milk will slop off the container 10. For connecting particular sensors to the container 10 for monitoring the frothing process, further contacts, plugs and sockets may be provided between the housing 2 and the base portion 3, although not shown.
However, the acoustic damping of the frothed milk in the container can also be measured from the base portion, since also the acoustic properties of the environment of the base portion will change, when the milk in the container 10 will change from an un-frothed to a frothed condition.
Fig. 4 illustrates a further embodiment in which the agitation means is provided on the inclined wall portion. The rod 22 for this purpose may be divided in two parts and may be coupled with a hinge 24. With such an arrangement of the agitation means 20 and the agitator 21 in addition to the inclined surface 12 also gravitational effects may be used for damping the oscillation of the milk or the liquid in the container 10. For such an embodiment, the heating element 30 may be provided on the bottom portion 13 of the container 10.
Fig. 4 further illustrates possible positions of a sensor element 18 which may be provided either in the direct vicinity of the container 10 or as an alternative in the base portion 3. These sensor elements may be based for example on ultrasonic effects, so that an acoustic damping between un-frothed milk and frothed milk can be compared in order to come to the conclusion that a frothing process is completed.
Further, in particular a sensor device in the vicinity of the container 10 may be used for determining the level of the liquid, in order to stop a heating or frothing process to avoid a slopping of milk. The coupling elements 23 and 53 can also be provided as beveled gears in order to avoid a hinged rod 22.
Fig. 5 illustrates a further exemplary embodiment, where the inclination of the inclined wall portion 12 is somewhat flatter with respect to the base portion 13 or a virtual horizontal plane, so that the total volume of a container 10 will be larger without the need to increase the total size of the milk frothing device 1.
As an alternative, Fig. 6 illustrates a further embodiment, where the inclined wall portion 12 is somewhat steeper with respect to the bottom portion 13, so that the total container shape is somewhat more like a taper. This further allows to increase the size of the heating element 30, so that the heating process may be shortened with respect to the total duration of the frothing process.
As an alternative embodiment, Fig. 7 illustrates a container having an inclined wall portion 12, which extends over the complete width of the bottom of the container 10, so that the bottom portion 13 can be considered as the deepest portion in the container 10. It should be noted that also other inclination angles can be provided in order to obtain the asymmetric arrangement of the agitation means and the inclined wall portion. In the embodiment of Fig. 7, the duct may be not orthogonal with respect to the here inclined surface through which the duct ducts.
Fig. 8 illustrates a further exemplary embodiment of the invention, according to which the wall portion of the container 10 is provided with elongated protrusions which may avoid the increasing of a liquid level during stirring or frothing. The protrusions may extend along a horizontal line. However, the protrusions may also be inclined in a screw like manner, in order to bring or keep down the liquid level during a stirring or frothing process. It should be noted that the negative inclination of the protrusions 19 with respect to the movement direction of the milk to be frothed may compensate the centrifugal forces and increasing level owing to the rotational movement in the depicted manner.
It should be noted that the term "comprising" does not exclude other elements or steps and the "a" or "an" does not exclude a plurality. Also elements described in this association with different embodiments may be combined.
It should be noted that the reference signs in the claims shall not be construed as limiting the scope of the claims.

Claims

Milk frothing device comprising:
a housing (2) including a container (10) for receiving the milk to be frothed, an agitation means (20),
wherein the container comprises a side wall (11), a bottom portion (13) and an inclined wall portion (12),
wherein the inclined wall portion being inclined with respect to the side wall and being confined by the side wall and the bottom portion,
wherein the container and the agitation means together form an asymmetrical arrangement.
Milk frothing device according to claim 1, wherein the agitation means (20) is positioned opposed to the inclined wall portion (12).
Milk frothing device according to any of claims 1 and 2, wherein the agitation means (20) comprises an agitator (21) and a rod (22), wherein the agitator is mounted to a first end of the rod, wherein the container (10) comprises a duct (14), wherein the rod extends through the duct so that the agitator (21) is provided within the container.
Milk frothing device according to claim 3, wherein the duct (14) is provided at the bottom portion (13) of the container (10).
Milk frothing device according to any of claims 3 and 4, wherein the rod (22) on a second end is provided with a first mechanical coupling element (23).
Milk frothing device according to any of claims 1 to 5, wherein the housing (2) further includes a heating element (30), the heating element being attached to at least the inclined wall portion (12).
Milk frothing device according to any of claims 1 to 6, wherein the inclined wall portion (12) is provided off center.
Milk frothing device according to any of claims 1 to 7, wherein the inclined wall portion (12) is flat.
Milk frothing device according to any of claims 1 to 8, wherein the agitation means (20) is provided off center of the container (10).
Milk frothing device according to any of claims 1 to 9, wherein the side wall portion (11) is of cylindrical form and the bottom portion (13) is flat, wherein the duct (14) is provided in the flat bottom portion.
Milk frothing device according to any of claims 5 to 10, wherein the milk frothing device (1) further comprises a releasable base portion (3) for receiving the housing (2), the base portion being provided with a driving means (50), wherein the diving means is provided with a second mechanical (53) coupling element, wherein the second coupling element is adapted for being coupled to the first coupling element (23) when the base portion receiving the housing.
Milk frothing device according to claim 11, wherein the housing (2) further includes a first electrical coupling element (11) connected to the heating element (30), wherein the base portion (3) comprises a second electrical connecting element (41), wherein the second electrical coupling element is adapted for being coupled to the first electrical coupling element when the base portion receiving the housing (2).
Milk frothing device according to claim 12, wherein the second electrical coupling element (41) is provided off center of the base portion (3).
Milk frothing device according to any of claims 12 and 13, wherein the housing includes the duct (14), the heating element (30), the first electrical coupling element (31) and the first mechanical coupling element (23) sealed in a dishwasher proof manner.
Milk frothing device according to any of claims 1 to 14, wherein milk frothing device further comprises a sensor (18) being capable of detecting a level of frothed milk.